Second harmonic surface response of a composite

Optical Second Harmonic Generation as a Probe of Surface Chemistry

Optical second harmonic generation (SHG) is the nonlinear conversion of two photons of frequency w to a single photon of frequency 2w which, in the electric dipole approximation, requires a noncentrosymmetric medium. The ability of noncentrosymmetric crystals to produce SHG has led to their implementation as frequency doublers in a wide variety of laser systems. SHG can also be obtained from th...

Surface-Barrier Effects in the Microwave Second-Harmonic Response of Superconductors in the Mixed State

We report on transient effects in the microwave second-order response of different type of superconductors in the mixed state. The samples have contemporarily been exposed to a dc magnetic field, varying with a constant rate of 60 Oe/s, and a pulsed microwave magnetic field. The time evolution of the signal radiated at the second-harmonic frequency of the driving field has been measured for abo...

the impact of training on second language writing assessment: a case of raters’ biasedness

چکیده هدف اول این تحقیق بررسی تأثیر آموزش مصحح بر آموزش گیرندگان براساس پایایی نمره های آنها در پنج بخش شامل محتوا ، سازمان ، لغت ، زبان و مکانیک بود. هدف دوم این بود که بدانیم آیا تفاوتهای بین آموزشی گیرندگان زن و مرد در پایایی نمرات آنها وجود دارد. برای بررسی این موارد ، ما 90 دانشجو در سطح میانه (متوسط) که از طریق تست تعیین سطح شده بودند انتخاب شدند. بعد از آنها خواستیم که درباره دو موضوع ا...

Surface-enhanced second-harmonic diffraction: Experimental investigation of selective enhancement.

Recent theoretical predictions demonstrating large enhancements of second-harmonic diffraction through the control of surface harmonic composition when the surface-plasmon polariton ~SPP! is excited on a corrugated silver surface have been investigated experimentally for the specular order. Interpretation of the mechanism of enhancement in terms of a three-step selective scattering process invo...

Surface-normal second harmonic emission from AlGaAs high-contrast gratings